Masarnau was born in Madrid 1805 to a family with close connections to the Spanish aristocracy and court. Life at Court was highly dependent on royal favour, and Masarnau's father, Santiago Masarnau Torres, who held a secretarial post, was obliged for unclear reasons to quit his privileges as a Gentleman of the Household in the 1820s. However, his son Santiago proved to be a musical prodigy and was able in his childhood to participate in the musical life of the Escorial, performing on the organ before King Ferdinand VII (including some of his own compositions) when he was only ten years old.
Following the family’s eviction from the Court, Santiago abandoned his original intentions of a career in engineering, and went to study music in Paris. He may have been influenced in the decision to leave Spain by political sympathies with the liberal insurgency that sought to depose the King in these years. For twenty years Masarnau divided his life between Paris, London and Madrid. In both Paris and London he was close to the Spanish composer José Melchor Gomis (1791–1836), himself a Spanish rebel living in exile. Gomis, who wrote some successful operas in Paris and got some respectful reviews from Hector Berlioz, was also active in London, and perhaps introduced Masarnau to London musical life. As a consequence of his studies and work in Paris and London, Masarnau became acquainted with Johann Baptist Cramer, Pierre-Alexandre Monsigny, Rossini, Paganini, and, it appears, Felix Mendelssohn, who is said to have admired Masarnau’s nocturne, Spleen.
Three Scherzini of Masarnau’s were published in London in 1828, at a time when Gomis was also publishing Spanish-style keyboard pieces there. Masarnau also became a friend of the English pianist and teacher Henry Ibbot Field (1797–1848), and around 1834 became a close friend of Charles-Valentin Alkan (as evidenced by an exchange of letters extending over forty years).[1] Alkan dedicated to Masarnau his 'Trois études de bravoure' op. 16 of 1837. While in Paris Masarnau became, at Rossini’s recommendation, the music teacher of the daughters of the Infante Prince Francisco de Paula.

Dedication to religion

In 1838 Masarnau had a profound religious experience which was to transform his life. As a consequence he determined to devote himself to the poor. In 1839 he came into contact with the Society of Saint Vincent de Paul in the Parisian parish of St. Louis d’Antin. The Society had been founded in 1833 by a charismatic 20-year old lawyer, Frédéric Ozanam (who was beatified in 1997), and was conceived as a Christian reaction to Saint-Simonism (which was attractive to many musicians including Ferdinand Hiller and Félicien David). The Society was dedicated to improving the lot of the poor; and although a lay Catholic organisation, it had a strictly male membership.
‘The rules adopted were very simple; it was forbidden to discuss politics or personal concerns at the meetings, and it was settled that the work should be the service of God in the persons of the poor, whom the members were to visit at their own dwellings and assist by every means in their power. The service of the members was to embrace, without distinction of creed or race, the poor, the sick, the infirm, and the unemployed.’ [2]
Masarnau devoted himself to the Society and became treasurer of the St. Louis d’Antin chapter. During this period he turned more to the composition of Church music than of salon items.
When Masarnau returned permanently to Spain in 1843 he remained concerned with music, teaching in his brother’s school, and contributing to a number of critical and artistic journals. But his main work was the establishment of the Society in his own country. This proved however not to be straightforward – the Spaniards were suspicious of this ‘foreign’ organisation and of its apparently ‘secular’ nature. Eventually in 1850 the Society in Spain was formally founded with the support of Pope Gregory XVI, after which it grew dramatically. Its success apparently aroused some political opposition - in 1868 the Society was forcibly dissolved by the Spanish state and its property seized. In 1874 the Society in Spain was allowed to re-establish itself, and Masarnau continued to lead it until his death in 1882.
He was made a candidate for beatification in 1999.[3]

Source: wikipedia